A lot of prior embodiments and a lot of knowledge is available in the art of to automated spool exchanges.
U.S. Pat. No. 4,477,033 is disclosing a winding machine for the continuous winding of flexible material on spools mounted on first and second independently operable spindles. Once a first spool has been filled, the flexible material is transferred to the second spool. On this second spool, close to the core, in the flange of the spool, is a grabber and cutter mechanism positioned. So the flexible material is only grabbed and cut once it is in contact with the second spool. The grabber and cutter mechanism comprise a piston, a piston cylinder, an arm and a movable flange. The building of this grabber and cutter mechanism in or on the spools complicates the embodiment. In addition, this embodiment only allows to transfer the flexible material from the first spool to the second spool and vice versa.
U.S. Pat. No. 4,938,428 discloses a wire winding system with a plurality of stations. Each station has a single take-up turntable driven by a variable speed motor. A mobile transfer cart is moveable to a selected station to carry out a wire transfer. The wire is transferred from the full spool on the turntable to the mobile transfer cart. The full spool is removed and replaced by an empty spool. Thereafter the mobile transfer cart effects the transfer of the winding wire to the empty spool on the turntable.
U.S. Pat. No. 4,971,264 discloses a method and apparatus for the continuous changing of reels on continuously operating stationary winding stations for strand-like material. In order to initiate a reel exchange, a full reel and an empty reel are connected to one another by means of a rotatable arm. The arm rotates and puts the full reel in place of the empty reel and vice versa, while the strand-like material is still being wound on the full spool. The strand-like material is cut and fixing and winding upon the empty reel can start. Thereafter the full reel and the rotatable arm are removed from the winding position. The connection of the full reel and the empty reel during continuous winding operation as well as the removal of the full spool also during continuous winding operation requires a rather complex mechanism.
DE-A1-38 10 875 discloses an improvement to the embodiment with the rotatable arm of U.S. Pat. No. 4,971,264. The rotatable arm is installed on a rail and is moveable along a series of winding stations. Only one rotatable arm mechanism is required for a plurality of winding stations.
GB 1207321 and GB 1456638 both disclose methods of transferring a wire or a strand from one spool to another spool. In GB 1207321 the uncut wire is snagged on the shaft of the empty spool and only thereafter the wire is cut. Similarly, in GB 1456638 the uncut strand is caught between catcher plates adjacent one of the flanges of the empty spool. These methods have two drawbacks. A first drawback is that after the wire or strand has been snagged or caught and cut, the trailing end of the wire or strand is relatively long since this trailing end bridges the distance between the two spools. As long as the full spool is still rotating, this long trailing end may cause problems. A second drawback is experienced during unwinding. Since the leading end of the wire or strand is caught either on the shaft of the empty spool or between catcher plates, the wire or strand cannot be kept on or near the core of the spool until the very last winding. On the contrary, a relatively long loose end is formed. This long loose end is often referred to as a ‘pig tail’ and is to be avoided.